The invention relates to a method for transmitting or delivery of a short message service (SMS) message to a mobile terminal. More specifically the invention relates to a method and system for identifying and/or preventing unauthorised delivery of an SMS mobile terminated message.
The sending and receiving of SMS-messages has become a popular way of communication. The SMS delivery service provides a mechanism for transmitting short messages to and from SMS-capable terminals, such as wireless handsets and personal computers via the signalling component of wireless communication networks. Signalling is based on signalling system no. 7 (SS.7) which is defined as a telecommunications industry standard signalling protocol. The SMS-service makes use of the SS.7 mobile application part (MAP), which defines the methods and mechanisms of signalling communication in mobile or wireless networks. The MAP protocol utilizes the transaction capabilities application part (TCAP) component of the SS.7 protocol. Both North American and European standards bodies have defined a MAP layer using the services of the SS.7 TCAP component. The North American standard is published by Telecommunication Industry Association and is referred to as IS-41 MAP, while the European standard is defined by the European Telecommunication Standards Institute (ETSI) and is referred to as GSM MAP. Below, the term SMS-network is used to identify all communication networks, including e.g. GPRS or UMTS networks, that allow delivery of SMS-messages to SMS-capable terminals.
The SMS-infrastructure employs a short message service centre (SMSC) that functions as a store and forward platform for SMS-messages. Hereinafter the term SMSC will be used for any platform in an SMS-network with identical, similar or equivalent functions as that of an SMSC. If an SMS-message is received at the SMSC it is stored and subsequently a delivery attempt to a mobile terminal is made. If delivery of the SMS-message is not possible, the SMS-message is stored at the SMSC until the destination for the SMS-message becomes available.
The delivery of SMS-messages in an SMS-network comprises two phases. In the first phase information of the mobile terminal is requested from a Home Location Register (HLR), hereinafter also referred to as HLR-request. This information may comprise the location of the mobile terminal, such as the mobile switching station (MSC) or serving GPRS support node (SGSN) in case of a GPRS network and alternative identifications of the mobile terminal, such as the local mobile station identifier (LMSI) and/or the international mobile station identifier (IMSI). In the second phase the SMS-message itself is delivered to the mobile terminal. The time span between these two phases typically is in a range between a few seconds and several minutes.
Currently, the first and second phase in the delivery of SMS-messages over an SMS-network to a mobile terminal cannot be separately controlled at the receiving end, i.e. at the terminating HLR and/or MSC. Information on the HLR-request does e.g. not provide one with the opportunity to control the delivery of the SMS-message itself.